Enhanced coagulation method for removing microplastics in water

Abstract

An enhanced coagulation method for removing microplastics in water is provided. First, a certain amount of inorganic suspended particles are added to microplastic wastewater to increase the number of particles and thereby improve a collision probability among the particles; and then a natural polymer flocculant and a polysilicic acid are added. The polysilicic acid is used as coagulant aid, so that the three materials can comprehensively achieve the purpose of removing the microplastics in the wastewater. The enhanced coagulation method can combine respective characteristics and advantages of the three materials, so that the three materials can mutually complement each other and give full play to the role of charge neutralization and bridging and net capturing, strengthen the sedimentation performance and enhance the actual microplastic removal effect. Therefore, it is a green and environmentally-friendly enhanced coagulation technology.

What is claimed is: 
     
       1. An enhanced coagulation method for removing microplastics in water, using a microplastic remover;
 wherein the microplastic remover comprises: inorganic suspended particles, a natural polymer based flocculant, and a polysilicic acid; 
 wherein the inorganic suspended particles comprise one selected from the group consisting of kaolin clay, attapulgite clay, montmorillonite, and talcum powder; 
 wherein the natural polymer based flocculant comprises one selected from the group consisting of modified starch, chitosan, cellulose, modified cellulose, lignin, and lignin derivatives; 
 wherein the enhanced coagulation method comprises: adding the inorganic suspended particles into water containing microplastics, stirring, and then adding the natural polymer based flocculant and the polysilicic acid simultaneously; 
 wherein a content of the microplastics is in a range of 1.0 to 5.0 micrograms per liter (mg/L); 
 wherein a dosage of the inorganic suspended particles is in a range of 1.0 to 3.0 mg/L; 
 wherein a dosage of the natural polymer based flocculant is in a range of 0.5 to 2.0 mg/L; and 
 wherein a dosage of the polysilicic acid is in a range of 5.0 to 10.0 mg/L. 
 
     
     
       2. The enhanced coagulation method according to  claim 1 , wherein the microplastics comprise one selected from the group consisting of polyvinyl chloride, polypropylene, polyethylene, and polystyrene; and a particle size of the microplastics is in a range of 100 nanometers to 500 micrometers. 
     
     
       3. An application method of the enhanced coagulation method according to  claim 1 , wherein the enhanced coagulation method is applied to remove microplastics in wastewater, and the wastewater is one selected from one of micro-polluted surface water, organic wastewater, acidic wastewater, and alkaline wastewater.